what is it that causes rough idle , when you are stopped in a red light, then ehn you try to star the engine dies,

...any number of things can cause this, but I'd start with a New air filter, lot of could be's 1.)PCV valve that little goodie that connects the valve conver to the intake. 2.) incorrect signal from computer 3.) throttle position sensor 4,) vacuum leak

Sounded like it was jumping or clunking like did it? hmmm...if so,it just might be an Engine mount or bad belts and in need of a Tune up such as new points,plug & filter... Also wiring is an issue much of the time in these K cars...take out the plugs,filter and points if possible do a Sun machine check on it. I merely installed a New engine mount when mine did this and that took care of it for mine...I also did a tune up. Compression can play into this sort of thing on ANY car though...engine seals or bad pistons.

vacuum leaks and disconnected hoses or poorly connected wires are also possible...I would start with taking off air cleaner cover but be careful not to disconnect any tubes or wires when going under the air cleaner,also reattachment is HIGHLY important when affixing it back properly. Seek out a good Hoist or mechanic and look to see if you have any exhaust leaks near the Y pipe at the back of the motor underneath...if your low on compression...you may need some exhaust fixing or tightening. I just sold my Dodge...it had new exhaust and tires on it...they are good runners but K cars leak a lot,both cylinder head and exhaust like to,often on the K cars,in particular after awhile,IMO. Plus wiring harness' suck in 'em at firewall,but it is prolly due crappy mopar parts or whatever....used to be famous 4 it. I liked mopar but like walmart,it went south.Kmart?-sure. So just open ur mind...go look.THINK:---Sun machine'.